Previous studies in workers have found an association between lead exposure and high blood pressure, atherosclerosis (hardening of the arteries), kidney disease and gout.

In this new study, male rats were given drinking water containing low levels of lead for 16 weeks, resulting in modest increases in the amount of lead in their blood. The lead exposure was associated with weight loss, increased blood pressure, a decline in kidney function, greater urinary protein, and increased scarring in the renal capillary system.

Researchers at the University of Florida said the most striking finding was that the low level lead exposure worsened kidney tissue disease. They published their findings online in the American Journal of Physiology-Renal Physiology.

"This study examined the effect of mild, chronic lead intoxication in an experimental model of chronic renal disease. The dose of lead administered resulted in mild toxicity. The degree of lead poisoning was sufficient to cause higher blood pressure and accelerate the progression of renal [kidney] failure," senior researcher Richard J. Johnson said in a prepared statement.

More information

The U.S. Agency for Toxic Substances & Disease Registry has more about lead.